Tympanostomy tube delivery device with rotatable flexible shaft

ABSTRACT

An instrument comprises a shaft assembly, a handpiece body, and a drive assembly. The shaft assembly comprises a plurality of coaxially arranged shafts and a tympanostomy tube. The shaft assembly further includes a flexible section. The shaft assembly extends distally from the handpiece body. The drive assembly is operable to drive the shafts of the shaft assembly in a predetermined sequence to deploy the tympanostomy tube. One or more of the shafts are configured to translate along the flexible section of the shaft assembly as a part of the predetermined sequence to deploy the tympanostomy tube.

BACKGROUND

Some children may exhibit recurrent episodes of otitis media and/orotitis media with effusion. Treatment of severe cases may involve theplacement of a pressure equalization tube or tympanostomy tube throughthe tympanic membrane to provide adequate drainage of the middle ear byproviding fluid communication between the middle and outer ear. Inparticular, such a tube may provide a vent path that promotes drainageof fluid from the middle ear via the Eustachian tube and may thus reducestress imposed on the tympanic membrane from pressure within the middleear. This may further reduce the likelihood of future infections andpressure induced ruptures of the tympanic membrane. Pressureequalization tubes may fall out spontaneously within about a year ofplacement. Exemplary pressure equalization tube delivery systems aredisclosed in U.S. Pat. No. 8,052,693, entitled “System and Method forthe Simultaneous Automated Bilateral Delivery of Pressure EqualizationTubes,” issued Nov. 8, 2011, the disclosure of which is incorporated byreference herein. Additional exemplary pressure equalization tubedelivery systems are disclosed in U.S. Pat. No. 8,249,700, entitled“System and Method for the Simultaneous Bilateral Integrated TympanicDrug Delivery and Guided Treatment of Target Tissues within the Ears,”issued Aug. 21, 2012, the disclosure of which is incorporated byreference herein. Still additional exemplary pressure equalization tubedelivery systems are disclosed in U.S. Pub. No. 2011/0015645, entitled“Tympanic Membrane Pressure Equalization Tube Delivery System,”published Jan. 20, 2011, the disclosure of which is incorporated byreference herein.

Insertion of a pressure equalization tube may be performed using generalanesthesia in some cases, which may require additional resources such asan operating room, the presence of an anesthesiologist, and time in arecovery room. Furthermore, the use of general anesthesia may includecertain risks that a patient may or may not be comfortable withundertaking. Some pressure equalization tube delivery systems andmethods provide a local anesthetic through iontophoresis. Examples ofsuch systems and methods are disclosed in U.S. Pub. No. 2010/0198135,entitled “Systems and Methods for Anesthetizing Ear Tissue,” publishedAug. 5, 2010, the disclosure of which is incorporated by referenceherein. Additional examples of such systems and methods are disclosed inU.S. Pat. No. 8,192,420, entitled “Iontophoresis Methods,” issued Jun.5, 2012, the disclosure of which is incorporated by reference herein.

While a variety of pressure equalization tube delivery systems andmethods have been made and used, it is believed that no one prior to theinventor(s) has made or used an invention as described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

It is believed the present invention will be better understood from thefollowing description of certain examples taken in conjunction with theaccompanying drawings, in which like reference numerals identify thesame elements and in which:

FIG. 1 depicts a perspective view of an exemplary pressure equalizationtube delivery device (PETDD);

FIG. 2 depicts a perspective view of the PETDD of FIG. 1, with a housinghalf omitted;

FIG. 3 depicts an exploded elevational view of actuation features of thePETDD of FIG. 1;

FIG. 4 depicts a perspective view of the distal end of a dilator of theactuation features of FIG. 3;

FIG. 5 depicts a perspective view of the distal end of a shield tube ofthe actuation features of FIG. 3;

FIG. 6 depicts a perspective view of the distal end of a pusher of theactuation features of FIG. 3;

FIG. 7 depicts a perspective view of the distal end of a piercer of theactuation features of FIG. 3;

FIG. 8 depicts a cross-sectional side view of the actuation features ofFIG. 3 with an exemplary pressure equalization (PE) tube;

FIG. 9 depicts a displacement and operational diagram associated withthe actuation features of FIG. 3;

FIG. 10 depicts an exploded perspective view of a trigger mechanism ofthe actuation features of FIG. 3;

FIG. 11 depicts a perspective view of the proximal side of a pawl of thetrigger mechanism of FIG. 10;

FIG. 12 depicts a perspective view of the distal side of the pawl ofFIG. 11;

FIG. 13 depicts a perspective view of the proximal underside of a buttonactuator of the trigger mechanism of FIG. 10;

FIG. 14 depicts a bottom plan view of the trigger mechanism of FIG. 10,showing the pawl engaged with the camshaft;

FIG. 15A depicts a cross-sectional view of the trigger mechanism of FIG.10, taken along line 15-15 of FIG. 14, showing the pawl engaged with thecamshaft;

FIG. 15B depicts a cross-sectional view of the trigger mechanism of FIG.10, taken along line 15-15 of FIG. 14, showing the pawl disengaged fromthe camshaft, with the button actuator omitted;

FIG. 16A depicts a cross-sectional view of the pawl and button actuatorof FIGS. 11 and 13, taken along line 16-16 of FIG. 15A, showing thebutton actuator arresting the pawl;

FIG. 16B depicts a cross-sectional view of the pawl and button actuatorof FIGS. 11 and 13, taken along line 16-16 of FIG. 15A, showing thebutton actuator translated laterally to enable movement of the pawl;

FIG. 17 depicts a perspective view of the proximal side of an exemplaryPE tube suitable for delivery by the PETDD of FIG. 1;

FIG. 18 depicts a perspective view of the distal side of the PE tube ofFIG. 17;

FIG. 19 depicts a distal elevational view of the PE tube of FIG. 17;

FIG. 20 depicts a side elevational view of the PE tube of FIG. 17,positioned within a tympanic membrane;

FIG. 21 depicts a perspective view of an exemplary alternative PETDDhaving a bendable and rotatable shaft assembly;

FIG. 22 depicts a side elevational view of the PETDD of FIG. 21 with analternative position of the shaft assembly shown in phantom;

FIG. 23 depicts a perspective view of the PETDD of FIG. 21, with ahousing half omitted;

FIG. 24 depicts an enlarged perspective view of the shaft assembly ofthe PETDD of FIG. 21;

FIG. 25 depicts a cross-sectional front view of the shaft assembly ofFIG. 24, with the cross-section taken along line 25-25 of FIG. 24;

FIG. 26 depicts a cross-sectional front view of the shaft assembly ofFIG. 24, with the cross-section taken along line 26-26 of FIG. 24;

FIG. 27 depicts a cross-sectional side view of the shaft assembly ofFIG. 24, with the cross-section taken along line 27-27 of FIG. 24; and

FIG. 28 depicts a side elevational view of the shaft assembly of FIG. 23in contact with a tympanic membrane.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the invention may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presentinvention, and together with the description serve to explain theprinciples of the invention; it being understood, however, that thisinvention is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the technology shouldnot be used to limit its scope. Other examples, features, aspects,embodiments, and advantages of the technology will become apparent tothose skilled in the art from the following description, which is by wayof illustration, one of the best modes contemplated for carrying out thetechnology. As will be realized, the technology described herein iscapable of other different and obvious aspects, all without departingfrom the technology. Accordingly, the drawings and descriptions shouldbe regarded as illustrative in nature and not restrictive.

It is further understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Thefollowing-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims.

I. Exemplary Pressure Equalization Tube Delivery Instrument

As noted above, a pressure equalization (PE) tube may be delivered tothe tympanic membrane (TM) of a patient as a way of treating, forexample, otitis media. In some instances, a delivery instrument may beused to insert PE tubes in the tympanic membrane (TM) without the use ofgeneral anesthesia. FIG. 1 shows an exemplary pressure equalization tubedelivery device (PETDD) (100) that may be used in such procedures. Itshould be understood that PETDD (100) may be used with an endoscope toprovide visualization of the tympanic membrane (TM) during use of PETDD(100). It should also be understood that a patient may receive localanesthesia at the tympanic membrane (TM) through a process ofiontophoresis before PETDD (100) is actuated to deploy a PE tube. By wayof example only, such iontophoresis may be provided in accordance withat least some of the teachings of U.S. Pub. No. 2010/0198135, thedisclosure of which is incorporated by reference herein; and/or inaccordance with at least some of the teachings of U.S. Pat. No.8,192,420, the disclosure of which is incorporated by reference herein.Other suitable ways in which PETDD (100) may be used will be apparent tothose of ordinary skill in the art in view of the teachings herein.

As shown in FIG. 1, PETDD (100) of this example comprises a handpiece(102) and a shaft assembly (115) extending distally from handpiece(102). Hanpdiece (102) is formed by two housing (104) halves that arejoined together and that include internal features configured to supportvarious components of PETDD (100) as will be described below. Handpiece(102) is configured to be handheld, such that an operator may fullyoperate PETDD (100) using a single hand. A pushbutton (106) is slidablydisposed in housing (104) and includes exposed portions extendinglaterally from each side of handpiece (102). Pushbutton (106) isoperable to be pushed along a path that is transverse to handpiece (102)in order to actuate PETDD (100) as will be described in greater detailbelow. A pull-pin (108) extends distally from handpiece (102) and isconfigured to prevent pushbutton (106) from being actuated, therebypreventing PETDD (100) from being actuated, so long as pull-pin (108) isdisposed in handpiece (102). Pull-pin (108) is nevertheless removablefrom handpiece (102) to effectively unlock pushbutton (106) and therebyenable actuation of PETDD (100). Shaft assembly (115) of the presentexample includes a cannula (120) comprising an elongate tube having aclear tip member (122) at the distal end of cannula (120). Clear tipmember (122) is configured to contact a patient's tympanic membrane (TM)while enabling visualization of the distal end of cannula (120). In someversions, tip member (122) is formed of a soft or elastomeric materialsuch as rubber, soft plastic, etc. This may dampen vibrations that mightotherwise be transmitted from cannula (120) to the patient's tympanicmembrane (TM) during firing of PETDD (100). In addition or in thealternative, tip member (122) may include some other kind of dampeningfeature as will be apparent to those of ordinary skill in the art inview of the teachings herein.

As can be seen in FIG. 2, housing (104) supports a camshaft (130) andvarious other components. Camshaft (130) includes a dilator track (132),a shield tube track (134), a stopper track (137), a pusher track (136),and a piercer track (138). Tracks (132, 134, 136, 137, 138) are formedas recesses in camshaft (130) and each track (132, 134, 136, 137, 138)has a unique configuration in order to provide a particular sequence ofoperation of translating components as will be described in greaterdetail below. A torsion spring (140) is coupled to the proximal end ofcamshaft (130). Torsion spring (140) is also grounded against housing(104). Torsion spring (140) resiliently provides a rotational bias tocamshaft (130). In particular, torsion spring (140) urges camshaft (130)to rotate in the clockwise direction (viewed from the distal end ofPETDD (100) toward the proximal end of PETDD (100)) about thelongitudinal axis of camshaft (130). As will be described in greaterdetail below (200), a trigger mechanism selectively resists suchrotation. While torsion spring (140) is used to bias camshaft (130) inthe present example, it should be understood that any other suitabletypes of components may be used to bias camshaft (130).

As shown in FIG. 3, various components are engaged with camshaft (130)and are thereby actuated by rotation of camshaft (130). In particular, adilator tube (150), a shield tube (160), a pusher tube (170), and apiercer (180) are all engaged with camshaft (130). Tubes (150, 160, 170)and piercer (180) are all coaxially disposed within cannula (120) ofshaft assembly (115). Piercer (180) is coaxially and slidably disposedwithin pusher tube (170), which is coaxially and slidably disposedwithin shield tube (160), which is coaxially and slidably disposedwithin dilator tube (150), which is coaxially and slidably disposedwithin cannula (120). Tubes (150, 160, 170) and piercer (180) alltranslate relative to cannula (120) in a particular sequence in order todeploy a PE tube as will be described in greater detail below. Thissequence is driven by rotation of camshaft (130).

A cam follower (152) is fixedly secured to the proximal end of dilatortube (150). Cam follower (152) includes a laterally projecting pin (154)that is disposed in dilator track (132), such that rotation of camshaft(130) causes cam follower (152) and dilator tube (150) to translate.Similarly, a cam follower (162) is fixedly secured to the proximal endof shield tube (160). Cam follower (162) includes a laterally projectingpin (164) that is disposed in shield tube track (134), such thatrotation of camshaft (130) causes cam follower (162) and shield tube(160) to translate. A cam follower (172) is fixedly secured to theproximal end of pusher tube (170). Cam follower (172) includes alaterally projecting pin (174) that is disposed in pusher tube track(136), such that rotation of camshaft (130) causes cam follower (172)and pusher tube (170) to translate. Finally, a cam follower (182) isfixedly secured to the proximal end of piercer (180). Cam follower (182)includes a laterally projecting pin (184) that is disposed in piercertrack (138), such that rotation of camshaft (130) causes cam follower(182) and piercer (180) to translate. Stopper track (137) is simplyannular in this example and includes a fixed elastomeric plug (135). Aninwardly protruding boss (not shown) of housing (104) is disposed instopper track (137). This boss remains disposed in stopper track (137)during rotation of camshaft (130).

As shown in FIG. 4, the distal end of dilator tube (150) includes aplurality of generally flexible leaves (156) that are separated bylongitudinally extending gaps (158). Leaves (156) are resiliently biasedto assume the inwardly deflected positioning shown in FIG. 4; but areoperable to flex outwardly from this positioning as will be described ingreater detail below. As shown in FIG. 5, the distal end of shield tube(160) simply includes a circular edge (166). As shown in FIG. 6, thedistal end of pusher tube (170) includes a distal face (176). In thepresent example, the difference between the inner diameter of pushertube (170) and the outer diameter of pusher tube (170) is greater thanthe difference between the inner diameter of shield tube (160) and theouter diameter of shield tube (160). Thus, distal face (176) presents amore prominent contact surface than circular edge (166). As shown inFIG. 7, the distal end of piercer (180) includes a sharp, multi-facetedpiercer tip (186) that is configured to pierce through a patient'stympanic membrane (TM). In the present example, piercer (180) alsoincludes a neck-down region (188) having a reduced diameter.

FIG. 8 shows the positioning of tubes (150, 160, 170), piercer (180),and PE tube (200) within cannula (120) before camshaft (130) startsrotating from a home position. As shown, piercer tip (186) of piercer(180) is positioned distal to leaves (156) of dilator tube (150), suchthat leaves (156) are positioned about neck-down region (188) of piercer(180). PE tube (200) is positioned within the distal end of shield tube(160), whose distal edge (166) is just proximal to leaves (156). Pushertube (170) is proximal to PE tube (200), with distal face (176) ofpusher tube (170) abutting the proximal end of PE tube (200). In thepresent example, PE tube (200) is resiliently biased to assume arivet-like shape presenting transverse petals (208) and a flange (206)(see FIG. 17-20). However, PE tube (200) is compressed against thisbias, thereby assuming a generally cylindraceous configuration, when PEtube (200) is disposed within shield tube (160) as shown in FIG. 8.

FIG. 9 depicts a sequence of operation that occurs upon rotation ofcamshaft (130) from a home position to an actuated position, wheretracks (132, 134, 136, 138) are shown developed into a flat pattern forpurpose of illustration. The sequence starts at the top region of FIG.9, which shows the distal end of clear tip member (122) contacting thepatient's tympanic membrane (TM). At this stage, tubes (150, 160, 170),piercer (180), and PE tube (200) are at the positions shown in FIG. 8.Once camshaft (130) starts rotating at the urging of torsion spring(140), pins (154, 164, 174, 184) begin to ride along their respectivetracks (132, 134, 136, 138), such that piercer tip (186) and leaves(156) are driven distally through the patient's tympanic membrane (TM).While not directly shown in FIG. 8, it should be understood that tubes(160, 170) are also driven distally during this transition, though tubes(160, 170) remain proximal to clear tip member (122) at this stage. Ascamshaft (130) continues to rotate, piercer (180) begins retractingproximally while tubes (160, 170) continue to advance distally. Asshown, shield tube (160) spreads leaves (156) outwardly from theirdefault positions. This further dilates the puncture site in thetympanic membrane (TM). Shield tube (160) continues to contain PE tube(200) at this stage. As camshaft (130) continues to rotate, piercer(180) and dilator (150) retract proximally behind clear tip member(122). Shield tube (160) also begins to retract proximally, while pushertube (170) remains longitudinally stationary. This relative movementuncovers the distal end of PE tube (200), such that the resilient biasof petals (208) causes petals (208) to flex to transverse positions,thereby effectively forming a flange on the far side of the tympanicmembrane (TM). Piercer (180) eventually returns to the fully proximalposition, dilator (170) eventually returns to the fully proximalposition, and pusher tube (170) eventually reaches a fully distalposition. As camshaft (130) continues to rotate, shield tube (160)continues to retract proximally while pusher tube (170) remainslongitudinally stationary. This relative movement uncovers the proximalend of PE tube (200), such that the resilient bias of PE tube (200) isallowed to form flange (206) on the near side of the tympanic membrane(TM).

Camshaft (130) stops rotating when the inwardly protruding boss ofhousing (104) engages plug (135) in stopper track (137). The elastomericnature of plug (135) provides a relatively soft stop, such that plug(135) acts as a damper. This may reduce jolting of PETDD (100) whencamshaft (130) comes to a stop and/or may prevent camshaft (130) frommaking a popping or snapping sound when camshaft (130) comes to a stop.Upon completion of the above described sequence shown in FIG. 9, cannula(120) is withdrawn from the patient's ear, leaving the actuated PE tube(200) in place in the patient's tympanic membrane (TM). Petals (208) andflange (206) cooperate to maintain the position of PE tube (200) in TM,while the passageway (204) formed by the interior of PE tube (200) (seeFIGS. 8 and 17-20) provides a path for fluid communication (e.g.,venting) between the patient's middle ear and outer ear. This fluid pathfurther provides pressure equalization between the patient's middle earand outer ear and/or promotes drainage of fluid from the middle ear viathe Eustachian tube.

As noted above, PETDD (100) of the present example includes a triggermechanism that is configured to selectively resist rotation of camshaft(130) by torsion spring (140). As best seen in FIGS. 10-16B, the triggermechanism of this example comprises a pawl member (190) that selectivelyengages pushbutton (106) and camshaft (130). Pawl member (190) includeslaterally extending pins (192) that couple pawl member (190) withhousing (104). While housing (104) prevents pawl member (190) frommoving laterally within housing (104), housing (104) permits pawl member(190) to pivot freely about pins (192) within housing (104). Pawl member(190) includes a distally facing boss rib (194) that extends vertically.Pawl member (190) also includes a pull-pin opening (196) and aproximally facing pawl ridge (198). Boss rib (194) is configured toselectively engage a proximally facing boss rib (107) of pushbutton(106) as will be described in greater detail below. Pull-pin opening(196) is configured to receive pull-pin (108), which assists to preventpawl member (190) from pivoting about pins (192) when pull-pin (108) isdisposed in pull-pin opening (196). Pawl ridge (198) includes chamferedlateral faces (199) and is configured to selectively engage a retentionfeature (131) of camshaft (130). In particular, when pawl member (190)is in a first position as shown in FIGS. 14, 15A, and 16A, pawl ridge(198) is engaged with retention feature (131) and prevents camshaft(130) from rotating despite the rotational bias provided by torsionspring (140). When pawl member (190) is pivoted to a second position asshown in FIGS. 15B and 16B, pawl ridge (198) disengages retentionfeature (131), enabling camshaft (130) to rotate under the influence oftorsion spring (140) to provide the sequence of operation describedabove.

As best seen in FIGS. 10 and 13, pushbutton (106) includes a pull-pinopening (109) that is configured to receive pull-pin (108). Pushbutton(106) is prevented from translating laterally relative to housing (104)when pull-pin (108) is disposed within pull-pin opening (109). Pull-pin(108) thus provides a lockout for pushbutton (106). To unlock pushbutton(106), pull-pin (108) may be pulled distally out of housing (104). Asnoted above, pushbutton (106) also includes a proximally facing boss rib(107) that extends vertically. When pushbutton (106) is laterallycentered within housing (104), boss rib (107) engages boss rib (194), asshown in FIGS. 15A and 16A. This engagement prevents pawl member (190)from pivoting distally about pins (192). Pushbutton (106) and pawlmember (190) together thus effectively lock camshaft (130) whenpushbutton (106) is laterally centered within housing (104).

When pushbutton (106) is laterally displaced relative to housing (104)(i.e., when a user depresses an exposed portion of pushbutton (106)laterally relative to housing (104)), bosses (107, 194) disengage suchthat pushbutton (106) no longer blocks pivoting of pawl member (190).Due to the torsional bias of camshaft (130), the ramped configuration ofretention feature (131), and the chamfered lateral faces (199) of pawlridge (198), camshaft (130) forces pawl member (190) to pivot out of theway to the position shown in FIGS. 15B and 16B when pushbutton (106) isno longer blocking pawl member (190). This enables camshaft (130) tocomplete the operational drive sequence described above. Whilepushsbutton (106) is depicted as being pushed in one lateral direction,it should be understood that the same triggering operation may beprovided when pushbutton (106) is pushed in the opposite lateraldirection from the center position. With portions of pushbutton (106)being exposed through housing (104) on each side of handpiece (102),this allows the operator to select which side of pushbutton (106) topress.

It should be understood that the foregoing components, features, andoperabilities of PETDD (100) are merely illustrative examples. A PETDD(100) may include various other features in addition to or in lieu ofthose described above. By way of example only, any of the devices hereinmay also include one or more of the various features disclosed in any ofthe various references that are incorporated by reference herein. Someadditional merely illustrative variations of PETDD (100) will bedescribed in greater detail below, while other variations of PETDD (100)will be apparent to those of ordinary skill in the art in view of theteachings herein.

II. Exemplary Pressure Equalization Tube

FIGS. 17-20 show PE tube (200) in greater detail. PE tube (200) of thisexample includes a cylindraceous body (202) that defines a passageway(204). A flange (206) is located at the proximal end of body (202) whilea set of petals (208) are located at the distal end of body (202).Flange (206) includes a plurality of inwardly directed recesses (207).Recesses (207) are configured to facilitate flexing of flange (206) froman outwardly extended position to a generally cylindraceous positionwhere the material forming flange (206) extends longitudinally. Whilethree recesses (207) are shown, it should be understood that any othersuitable number of recesses (207) may be provided. Similarly, whilethree petals (208) are shown, it should be understood that any othersuitable number of petals (208) may be provided.

PE tube (200) is formed of a resilient material that is biased to assumethe rivet like configuration shown in FIGS. 17-20. However, flange (206)and petals (208) may be flexed inwardly toward the longitudinal axis ofbody (202) to provide PE tube (200) with a cylindraceous configuration.In particular, flange (206) and petals (208) may be flexed such thattheir outer surfaces are at the same radial distance from thelongitudinal axis as the outer perimeter of body (202). This radialdistance may be slightly less than the radial distance associated withthe inner diameter of shield tube (160), such that PE tube (200) maycollapse to fit within shield tube (160). When PE tube (200) is disposedin a tympanic membrane (TM), petals (208) are located medially (i.e., onthe middle ear side) while flange (206) is located laterally (i.e., onthe outer ear side). By way of example only, PE tube (200) may also beconfigured in accordance with at least some of the teachings of U.S.Pat. App. No. 13/800,113, entitled “Tympanic Membrane PressureEqualization Tube,” filed on Mar. 13, 2013, published as U.S. Pub. No.2014/0094733 on Apr. 3, 2014, the disclosure of which is incorporated byreference herein. Other suitable forms that PE tube (200) may take willbe apparent to those of ordinary skill in the art in view of theteachings herein.

III. Exemplary Pressure Equalization Tube Delivery Instrument withBendable and Rotatable Shaft Assembly

Those of ordinary skill in the art will appreciate that the tympanicmembrane (TM) may extend along a plane that is oblique to the directionof insertion of PETDD (100). In other words, the plane of the tympanicmembrane (TM) may be obliquely angled relative to the longitudinal axisof shaft assembly (115). By way of example only, the tympanic membrane(TM) may define an angle between approximately 79 degrees andapproximately 54 degrees with the longitudinal axis of shaft assembly(115). This oblique orientation of the tympanic membrane (TM) may posedifficulties with respect to some versions of a PETDD (100) that has aflat tip and/or a straight shaft assembly (115). For instance,inadequate apposition between the distal edge of tip member (122) andthe tympanic membrane (TM) may lead to unsuccessful deployment of PEtube (200). This may prompt some operators of PETDD (100) to applysignificant pressure against the tympanic membrane (TM), to deform thetympanic membrane (TM) into a position of substantial apposition withthe flat-faced tip member (122) of PETDD (100). It may be desirable tomaximize the apposition between the distal edge of tip member (122) andthe tympanic membrane (TM), such as by enabling the distal edge of tipmember (122) to complement the orientation of the tympanic membrane (TM)as much as possible, without requiring an operator to apply significantpressure against the tympanic membrane (TM) in order to achieve adequateapposition.

A rigid shaft assembly (115) may also adversely impact the ergonomics ofPETDD (100) by forcing an operator to hold PETDD (100) at anuncomfortable angle to achieve a desired angle between shaft assembly(115) and the tympanic membrane (TM). Incorporating flexible and/orrotatable features into shaft assembly (115) may thus enhance theergonomics of PETDD (100). In particular, a flexible and/or rotatableshaft assembly (115) may enable an operator to hold PETDD (100) at amore comfortable angle while still maintaining proper orientation ofshaft assembly (115) relative to the patient's tympanic membrane (TM).Additionally, such features may facilitate positioning of an endoscopeand/or other instrument with shaft assembly (115) in the patient's earcanal, thus promoting visualization of the tympanic membrane (TM). Thefollowing examples include merely illustrative variations of PETDD (100)that may provide flexibility and/or rotatability in shaft assembly(115).

FIG. 21 depicts an exemplary alternative PETDD (300) having a bendableshaft assembly (315). All of the other components in this variation maybe the same as those described above for PETDD (100), unless otherwisenoted herein. As can be seen, PETDD (300) of this example comprises ahandpiece (302) and a shaft assembly (315) extending distally fromhandpiece (302). Hanpdiece (302) is formed by two housing (304) halvesthat are joined together and that include internal features configuredto support various components of PETDD (300) similarly as describedabove with respect to handpiece (102) of PETDD (100). Handpiece (302) isconfigured to be handheld, such that an operator may fully operate PETDD(300) using a single hand. A pushbutton (306) is slidably disposed inhousing (304) and includes exposed portions extending laterally fromeach side of handpiece (302). Pushbutton (306) is operable to be pushedalong a path that is transverse to handpiece (302) in order to actuatePETDD (300) similarly as described above with respect to pushbutton(106) of PETDD (100). A pull-pin (308) extends distally from handpiece(302) and is configured to prevent pushbutton (306) from being actuated,thereby preventing PETDD (300) from being actuated, so long as pull-pin(308) is disposed in handpiece (302). Pull-pin (308) is neverthelessremovable from handpiece (302) to effectively unlock pushbutton (306)and thereby enable actuation of PETDD (300).

As can be seen in FIGS. 21 and 22, shaft assembly (315) of the presentexample includes a cannula (320) comprising an elongate tube having abendable section (324), a thumbwheel (310), and a tip member (322) atthe distal end of cannula (320). Thumbwheel (310) is fixedly secured tocannula (320) where cannula (320) and handpiece (302) meet. As will bedescribed in greater detail below, thumbwheel (310) is operable torotate cannula (320) about the longitudinal axis of cannula (320)relative to handpiece (302) when acted upon by a user. In the presentexample, handpiece (302) includes a bushing (312) which both supportscannula (320) in handpiece (302) and permits cannula (320) to rotate. Insome versions, thumbwheel (310) may be fixedly secured to cannula (320)by adhesive bonding, over-molding, or any other means. Additionally, aproximal end of cannula (320) may include a flared end or othergeometric features to aid with attachment. Yet in other examples,thumbwheel (310) may be integral to cannula (320) such that the twoparts form a unitary part. Of course, thumbwheel (310) is entirelyoptional and may be eliminated in other versions.

As best seen in FIGS. 24-26, bendable section (324) comprises aplurality of cut outs (326), which define a plurality of ribs (328) oneither side of cannula (320). Cut outs (326) only extend through aportion of cannula (320) such that a solid longitudinally extendingmember (329) of cannula (320) remains. Longitudinally extending member(329) maintains lateral stability of cannula (320), yet cut outs (326)and ribs (328) operate cooperatively to permit cannula (320) to bendalong a plane as will be described in greater detail below. It should beunderstood that bendable section (324) as depicted shows merely oneexemplary geometry suitable to permit cannula (320) to bend. In otherexamples, bendable section (324) could have any other suitable designsuch as a fluid linkage and/or other bendable structure as will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Tip member (322) is configured to contact a patient's tympanic membrane(TM). In some versions, tip member (322) may be integral to cannula(320) such that cannula (320) and tip member (322) are of a unitarypart. In other versions tip, member (322) may be a separate componentfixedly secured to the distal end of cannula (320). In either case, tipmember (322) may be configured to be clear or opaque. Where clear, tipmember (322) may enable enhanced visualization of a patient's tympanicmembrane (TM). Although the distal end of tip member (322) is shown asbeing orthogonal relative to the longitudinal axis of cannula (320), itshould be understood that other distal end geometries may be used. Forinstance, the distal end of tip member (322) may be obliquely angledrelative to the longitudinal axis of cannula (320) to accommodatepatients with obliquely angled TM's. Examples of such obliquely angleddistal ends of tip member may be configured in accordance with at leastsome of the teachings of U.S. Pat. App. No. 13/804,553, entitled“Features to Improve and Sense Tympanic Membrane Apposition byTympanostomy Tube Delivery Instument,” filed on Mar. 14, 2013, thedisclosure of which is incorporated by reference herein. Of course, anyother suitable configuration of tip member (322) may be used as will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Cannula (320) and/or tip member (322) may be formed of the samematerials or different materials. For instance, in some versions cannula(320) and/or tip member (322) may be formed of a soft or elastomericmaterial such as rubber, soft plastic, nylon, polyether ether ketone(PEEK), etc. Yet in other versions cannula (320) and/or tip member (322)may be formed of a hard, more resilient material such as stainlesssteel, aluminum, or the like. In still other examples, cannula (320)could comprise a rigid material proximal to bendable section (324), aflexible material at bendable section (324), and a rigid material distalto bendable section (324). Alternatively, bendable section (324) couldbe formed of a malleable material. As yet another merely illustrativeexample, bendable section (324) may be formed of a plurality of short,rigid segments that are pivotally coupled together. When cannula (320)and/or tip member (322) is comprised of a soft or elastomeric material,such a material may dampen vibrations that might otherwise betransmitted from cannula (120) to the patient's tympanic membrane (TM)during firing of PETDD (300). In addition or in the alternative, tipmember (322) may include some other kind of dampening feature as will beapparent to those of ordinary skill in the art in view of the teachingsherein.

As can be seen in FIG. 23, housing (304) supports a camshaft (330) andvarious other components. Camshaft (330) includes a dilator track (332),a shield tube track (334), a stopper track (337), a pusher track (336),and a piercer track (338). Tracks (332, 334, 336, 337, 338) are formedas recesses in camshaft (330) and each track (332, 334, 336, 337, 338)has a unique configuration in order to provide the same particularsequence of operation as similarly described above with respect tocamshaft (130) of PETDD (100). A torsion spring (340) is coupled to theproximal end of camshaft (330). Torsion spring (340) is also groundedagainst housing (304). Torsion spring (340) resiliently provides arotational bias to camshaft (330). In particular, torsion spring (340)urges camshaft (330) to rotate in the clockwise direction (viewed fromthe distal end of PETDD (300) toward the proximal end of PETDD (300))about the longitudinal axis of camshaft (330). As was similarlydescribed above with respect to PETDD (100), a trigger mechanismselectively resists such rotation. While torsion spring (340) is used tobias camshaft (330) in the present example, it should be understood thatany other suitable types of components may be used to bias camshaft(330).

As similarly described above with respect to camshaft (130) of PETDD(100), various components are engaged with camshaft (330) and arethereby actuated by rotation of camshaft (330). In particular, a dilatortube (350), a shield tube (360), a pusher tube (370), and a piercer(380) are all engaged with camshaft (330). Tubes (350, 360, 370) andpiercer (380) are all coaxially disposed within cannula (320) such thattubes (350, 360, 370) and piercer (380) together form shaft assembly(315). Piercer (380) is coaxially and slidably disposed within pushertube (370), which is coaxially and slidably disposed within shield tube(360), which is coaxially and slidably disposed within dilator tube(350), which is coaxially and slidably disposed within cannula (320).Tubes (350, 360, 370) and piercer (380) all translate relative tocannula (320) in a particular sequence in order to deploy a PE tube aswas similarly described above. This sequence is driven by rotation ofcamshaft (330).

A cam follower (352) is fixedly secured to the proximal end of dilatortube (350). Cam follower (352) includes a laterally projecting pin (notshown) that is disposed in dilator track (332), such that rotation ofcamshaft (330) causes cam follower (352) and dilator tube (350) totranslate. Similarly, a cam follower (362) is fixedly secured to theproximal end of shield tube (360). Cam follower (362) includes alaterally projecting pin (not shown) that is disposed in shield tubetrack (334), such that rotation of camshaft (330) causes cam follower(362) and shield tube (360) to translate. A cam follower (372) isfixedly secured to the proximal end of pusher tube (370). Cam follower(372) includes a laterally projecting pin (not shown) that is disposedin pusher tube track (336), such that rotation of camshaft (330) causescam follower (372) and pusher tube (370) to translate. Finally, a camfollower (382) is fixedly secured to the proximal end of piercer (380).Cam follower (382) includes a laterally projecting pin (not shown) thatis disposed in piercer track (338), such that rotation of camshaft (330)causes cam follower (382) and piercer (380) to translate. Stopper track(337) is simply annular in this example and includes a fixed elastomericplug (335). An inwardly protruding boss (not shown) of housing (304) isdisposed in stopper track (337). This boss remains disposed in stoppertrack (337) during rotation of camshaft (330).

Although not shown, tubes (350, 360, 370) and piercer (380) have distalends configured similarly to the distal ends of tubes (150, 160, 170)and piercer described above. For instance, dilator tube (350) includes aplurality of flexible leaves (not shown) that are resiliently biasedinwardly. Likewise, the distal end of shield tube (360) and pusher tube(370) include a circular edge (not shown) and a distal face (not shown),respectively. Similar to distal face (176) discussed above, distal faceof pusher tube comprises a more prominent contact surface relative tocircular edge of shield tube (160). Additionally, piercer (180) includesa sharp multi-faceted piercer tip (not shown) that is configured topierce through a patient's tympanic membrane (TM). Although tubes (350,360, 370) and piercer (380) are described above as having distal endsthat are similar to those of tubes (150, 160, 170) and piercer (180), nosuch limitation is intended. Indeed, tubes (350, 360, 370) and piercer(380) may comprise any suitable distal end configurations as will beapparent to those of ordinary skill in the art in view of the teachingsherein.

In the present example, at least a portion of each tube (350, 360, 370)and piercer (380) is flexible. By way of example only, at least aportion of each tube (350, 360, 370) and piercer (380) may be formed ofnylon, PEEK, some other flexible polymer, a flexible metal, and/or anyother suitable flexible material(s) as will be apparent to those ofordinary skill in the art in view of the teachings herein. Such aflexible portion of each tube (350, 360, 370), and piercer (380) extendsthrough bendable section (324) of cannula (320). In addition to allowingbendable section (324) to flex along a plane, the flexible region(s) oftubes (350, 360, 370) and piercer (380) enable tubes (350, 360, 370) andpiercer (380) to translate longitudinally through bendable section (324)while bendable section (324) is in a bent state. In some versions, tubes(350, 360, 370) and piercer (380) each have a rigid distal end or rigiddistal portion, in addition to having a flexible region located proximalto the rigid distal end or portion. By way of example only, the rigiddistal end or rigid distal section of each tube (350, 360, 370) andpiercer (380) may be formed of a rigid metal, a rigid polymer, and/orany other suitable rigid material(s) as will be apparent to those ofordinary skill in the art in view of the teachings herein. It shouldalso be understood that a proximal section of each tube (350, 360, 370)and piercer (380) may be rigid, in addition to a distal portion ordistal end of each tube (350, 360, 370) and piercer (380) being rigid,with the intermediate region of the length of each tube (350, 360, 370)and piercer (380) being flexible. Various suitable combinations ofrigidity and flexibility in the construction of tubes (350, 360, 370)and piercer (380) will be apparent to those of ordinary skill in the artin view of the teachings herein.

Tubes (350, 360, 370) are configured to be used in conjunction with PEtube (200) as similarly described above with respect to PETDD (100). Inparticular, PE tube (200), tubes (350, 360, 370), and piercer (380) mayall be sequentially actuated within cannula (320). The particularsequence is controlled by tracks (332, 334, 336, 338) as camshaft (330)rotates and is substantially similar to the sequence described abovewith respect to FIG. 9. Thus, even though cannula (320) is bendable,PETDD (300) is still operable to penetrate a patient's tympanic membrane(TM) and deploy PE tube (200) using substantially the same mechanisms asthose described above with respect to PETDD (100). In other versions,PETDD (300) may be configured for use without PE tube (200). Forinstance, PETDD (300) may simply be used to puncture a patient'stympanic membrane (TM) for fluid collection or other similar procedures.

FIG. 22 shows that cannula (320) is bendable to a variety of angles. Byway of example only, cannula (230) may bend to achieve angles fromapproximately 0 degrees to approximately 60 degrees; or fromapproximately 0 degrees to approximately 45 degrees. In some versions,cannula (320) may be configured to be malleable such that it may be bentto a specific angular location and remain at that specific locationwithout a continuously applied force. Yet in other versions, cannula(320) may merely be flexible such that it may be sustained in aparticular angular location only when a continuous force is applied. Ineither case, such properties may be achieved by, at least in part, thematerials used for cannula (320), tubes (350, 360, 370), and/or piercer(380). For instance, to achieve malleable properties, cannula (320) maybe comprised of malleable alloys such as stainless steel alloys,aluminum alloys, shape memory alloys, or the like. Additionally, suchmalleable properties may be achieved with other materials such asmalleable plastics or polymers. Alternatively, to achieve propertiesthat render cannula flexible, non-malleable alloys or plastics may beused. Further, materials may be varied between cannula (320), tubes(350, 360, 370), and piercer (380) to render cannula (320) malleable,semi-malleable, or flexible. Of course, cannula (320), tubes (350, 360,370), and piercer (380) may be comprised of any suitable material tohave any suitable properties as will be apparent to those of ordinaryskill in the art in view of the teachings herein.

As can be seen in FIGS. 25-27, tubes (350, 360, 370) and piercer (380)extend through bendable section (324) of cannula (320) and areconfigured to bend as cannula (320) bends. It should be understood thattubes (350, 360, 370) and piercer (380) are configured such that theymay be sequentially actuated within cannula (320) even when cannula(320) is bent. In other words, cannula (320) tubes (350, 360, 370), andpiercer (380) are configured to maintain a neutral axis throughoutbendable section (324) such that each component maintains a consistentrelationship with tip member (322) as cannula (320) is bent. In someversions, lubricant may be included between cannula (320), tubes (350,360, 370), piercer (380) and cannula (320), although such lubricant isentirely optional.

As noted above, cannula (320) is rotatable via thumbwheel (310). Thus,cannula (320) is operable to both bend and rotate relative to itslongitudinal axis. In some versions, tubes (350, 360, 370) and piercer(380) may remain stationary while cannula (320) rotates. In some otherversions, thumbwheel (310) may be configured to rotate all or some oftubes (350, 360, 370) and/or piercer (380) in conjunction with cannula(320). Still in other versions, tubes (350, 360, 370) and/or piercertube (380) may be configured to be independently rotatable relative tocannula (320). For instance, piercer tube (380) may be independentlyrotatable to optimize piercing. Such a combination of bendability androatatability may increase visualization of, and access to, the tympanicmembrane (TM) of a patient. In an exemplary use of PETDD (300), cannula(320) may be pre-bent outside of a patient to account for an obliquelyoriented tympanic membrane (TM) of the patient. Cannula (320) may bethen inserted into the ear of the patient. An endoscope or other similardevice may be used for visualization of the patient's tympanic membrane(TM) as cannula (320) is inserted through the ear canal. As tip member(322) approaches the patient's TM, cannula (320) may be rotated to finetune the angle of tip member (322) to position tip member (322) intoproper alignment with the patient's tympanic membrane (TM). As can beseen in FIG. 28, cannula (320) may be further advanced such that tipmember (322) engages the patient's tympanic membrane (TM) in fullapposition. Pushbutton (306) may then be actuated by a user, and the PETube (200) may be delivered to the patient's tympanic membrane (TM). Insome other exemplary procedures, cannula (320) may be merely flexibleand the ear canal may be used to provide a force sufficent to bendcannula (320) such that it may be positioned into alignment with thepatient's tympanic membrane (TM). Of course, PETDD (300) may be used invarious other ways as will be apparent to those of ordinary skill in theart in view of the teachings herein.

IV. Miscellaneous

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Versions described above may be designed to be disposed of after asingle use, or they can be designed to be used multiple times. Versionsmay, in either or both cases, be reconditioned for reuse after at leastone use. Reconditioning may include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, someversions of the device may be disassembled, and any number of theparticular pieces or parts of the device may be selectively replaced orremoved in any combination. Upon cleaning and/or replacement ofparticular parts, some versions of the device may be reassembled forsubsequent use either at a reconditioning facility, or by a userimmediately prior to a procedure. Those skilled in the art willappreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, versions described herein may be sterilizedbefore and/or after a procedure. In some instances, the device issterilized using conventional ethylene oxide sterilization techniquesand systems. In some other instances, the device is placed in a closedand sealed container, such as a plastic or TYVEK bag; and the containerand device may then be placed in a field of radiation that can penetratethe container, such as gamma radiation, x-rays, or high-energyelectrons. The radiation may kill bacteria on the device and in thecontainer. The sterilized device may then be stored in the sterilecontainer for later use. A device may also be sterilized using any othertechnique known in the art, including but not limited to beta or gammaradiation, steam, etc.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

I/We claim:
 1. An instrument comprising: (a) a shaft assembly, whereinthe shaft assembly comprises a plurality of coaxially arranged shaftsand a tympanostomy tube, wherein the shaft assembly further includes aflexible section; (b) a handpiece body, wherein the shaft assemblyextends distally from the handpiece body; and (c) a drive assemblyoperable to drive the shafts of the shaft assembly in a predeterminedsequence to deploy the tympanostomy tube, wherein one or more of theshafts are configured to translate along the flexible section of theshaft assembly as part of the predetermined sequence to deploy thetympanostomy tube.
 2. The instrument of claim 1, wherein the shaftassembly is rotatable relative to the handpiece body.
 3. The instrumentof claim 2, further comprising a thumbwheel fixedly secured to the shaftassembly, wherein the thumbwheel is operable to rotate the shaftassembly.
 4. The instrument of claim 1, wherein the flexible sectioncomprises a relief pattern.
 5. The instrument of claim 4, wherein therelief pattern comprises a plurality of ribs and a longitudinallyextending section, wherein the plurality of ribs and the longitudinallyextending section define a plurality of cutouts.
 6. The instrument ofclaim 4, wherein the relief pattern is cut into at least one of theshafts of the shaft assembly.
 7. The instrument of claim 1, wherein theflexible section is malleable.
 8. The instrument of claim 1, wherein atleast one of the shafts of the shaft assembly comprises nylon.
 9. Theinstrument of claim 1, wherein at least one of the shafts of the shaftassembly comprises PEEK.
 10. The instrument of claim 1, wherein theshafts of the shaft assembly are operable to pierce a tympanic membraneof a patient and deploy the tympanostomy tube into the tympanic membraneof the patient.
 11. The instrument of claim 1, wherein the shafts of theshaft assembly are configured to bend within the flexible portion suchthat the predetermined sequence of the drive assembly is unaffected bythe bending.
 12. The instrument of claim 1, wherein a surface betweeneach shaft of the shaft assembly is coated with a lubricant.
 13. Theinstrument of claim 1, wherein the shaft assembly further comprises anouter cannula, wherein the outer cannula comprises a distal tip, whereinthe distal tip has a larger outer diameter than the outer cannula. 14.The instrument of claim 13, wherein distal tip of the outer cannula isunitarily formed in the outer cannula.
 15. The instrument of claim 15,wherein the outer cannula and the distal tip comprise nylon or PEEK. 16.An apparatus comprising: (a) a shaft assembly, wherein the shaftassembly comprises a plurality of coaxially arranged shafts and atympanostomy tube; (b) a handpiece body, wherein the shaft assemblyextends distally from the handpiece body, wherein at least a portion ofthe shaft assembly is rotatable relative to the handpiece body; and (c)a drive assembly operable to drive the shafts of the shaft assembly in apredetermined sequence to deploy the tympanostomy tube.
 17. Theapparatus of claim 16, wherein the shaft assembly further includes aflexible portion, wherein the shaft assembly is configured to bend atthe flexible portion.
 18. The apparatus of claim 17, wherein theflexible portion comprises a relief pattern cut into at least one of theshafts of the shaft assembly.
 19. The apparatus of claim 16, furthercomprising a thumbwheel, wherein the thumbwheel is operable to rotate atleast a portion of the shaft assembly relative to the handpiece body.20. An apparatus comprising: (a) a shaft assembly, wherein the shaftassembly comprises a plurality of coaxially arranged shafts and aflexible portion, wherein one of the shafts includes a piercing element,wherein a distal end of the shaft assembly is configured to fit in anear canal of a patient; (b) a handpiece body, wherein the shaft assemblyextends distally from the handpiece body; and (c) a drive assemblyoperable to drive the shafts of the shaft assembly in a predeterminedsequence to pierce a tympanic membrane with the piercing element;wherein the shaft assembly is configured to bend at the flexibleportion.